xserver: Branch 'master' - 11 commits

[Mark Kettenis]

> Date: Mon, 04 Nov 2013 10:15:40 -0800
> From: Ian Romanick <idr at freedesktop.org>
> 
> On 11/02/2013 10:09 AM, Jeremy Huddleston Sequoia wrote:
> > Why does this now require mesa 9.2.0? >= 9.0 doesn't build on OS X,
> > and I haven't had time to address the issue in mesa. I'm wondering if I
> > can just revert this and keep the old requirement for now since this
> > change seems to be related just to dri3 (which doesn't affect XQuartz
> > anyways).
> > 
> > -LIBGL="gl >= 7.1.0"
> > +LIBGL="gl >= 9.2.0"
> 
> This has nothing to do with DRI3.  It has to do with floating point
> configs for pbuffers in DRI2.  Mesa 9.2 is required because that is the
> version that adds __DRI_ATTRIB_FLOAT_BIT and
> __DRI_ATTRIB_UNSIGNED_FLOAT_BIT to dri_interface.h.  See Mesa commit
> c37c367.
> 
> If you'd like to submit a patch that will allow the server to gracefully
> disable GLX_ARB_fbconfig_float when the version of dri_interface.h is
> too old (or just stub it out for XQuartz), I'd be happy to review it.

That stuff is only used in glxdri2.c, which is only compiled in if
DRI2_AIGLX is defined.  Which I suppose isn't the case on OS X.  So
perhaps some configure magic is enough here, perhaps lowering the
requirements specifically for that platform?